Just share the information that I came across when testing my application.
The Facebook Graph API implements a speed limit as described on the page. Today I tried to get a feed on a Facebook page on CNN, and I got the following 500 error:
{"error":{"code":1,"message":"Please reduce the amount of data you're asking for, then retry your request"}}
This is the query I tried to check:
https://graph.facebook.com/v2.3/5550296508/feed?fields=id,actions,application,caption,created_time,description,from,icon,is_hidden,link,message,message_tags,name,object_id,picture,place,privacy,properties,source,status_type,story,story_tags,to,type,updated_time,with_tags,shares,likes.limit(50),comments.filter(stream).limit(50){attachment,created_time,from,id,like_count,message,message_tags,comments{attachment,created_time,from,id,like_count,message,message_tags}}&access_token=xxxxxxx